04 to 03 g35 engine swap

[jmoore6]

Any input would be appreciated..... I recently did a motor swap from an 04 g35sedan to an 03.... The 04 was rolled but it drove if you stuck your head out the door like ace ventura. The 03 had a hole in the block. Did some research and it seemed like a direct match. Mid production apparently they changed ecu's. So my 03 wont even crank starter, everything else appears to work. Did somemore research and spoke to a few people who seemed to thing I just needed to resync the 04 ecu to the 03 bcm with my consult3 programmer. it wont even detect my ecu.... neither does my obd2 scanner.... im looking into power and groung issues first since they must have made some changes somewhere in the harnesses. Any others thoughts and direction would be appreciated.

[joe603]

why not get an aftermarket ECU? Seems to be very custom anyway.. Feel free to browse the Factory Service Manuals to see if there are any differences.

[jmoore6]

Im thinking its wiring change. Like perhaps pins have been added deleted or swapped to accomodate the new ecu.... The 03 harness must not be 100% compatible. it plugs in fine but ita almost like ecu doesnt have power or data link is missing.

[joe603]

maybe look at the FSM for the 03 and compare to the 04?? Not sure honestly.

[jmoore6]

Yeah. Thats what ive been doing slowely. What i thinl i need is a pin out of smj and the three plugs in batt compartment . Thanks for your input.

[jmoore6]

Has no one in here done any transplants and ran into similar issues? Computer or canbus issues?

[jmoore6]

Ok so ive been reviewing the fsm's. All the fsm's for the G35 seem to show the same ecu and supporting harnesss's. which is like my 04...... However my 03 is slightly different. most of the connectors are the same that inter connect with each other however the ecu/bcm and ipcm are each diff. any ideas????? any ideas on where to find early production fsm's?